1. Field
One or more example embodiments relate to a mobile communication base station system, and more particularly, to a mobile communication base station system having a structure in which a digital unit and a radio unit are separated from each other.
2. Description of the Related Art
Recently, a separate structure, in which a digital unit which is a data processing part of a base station and a radio unit which is a wireless transmitting and receiving part of the base station are separated from each other to be placed in different areas and are connected to each other through an optical cable, is widely applied to a mobile communication base station system in response to a trend of decreasing a cell size in service coverage due to a rapid increase in mobile traffic along with traffic caused by an Internet service.
A standard protocol for communication between the digital unit and the radio unit in the mobile communication base station system with the separate structure includes a common public radio interface (CPRI) protocol, an open radio equipment interface (ORI) protocol, and an open base station architecture initiative (OBSAI) protocol. However, since the protocols only define standards for user data between the digital unit and the radio unit, standards defined individually for each manufacturer are used for control information, synchronization information, or the like. As a result, compatibility between digital units and radio units manufactured by different manufacturers is not guaranteed, and compatibility between organization and management (O&M) servers for controlling the digital units and radio units is also not guaranteed.
FIG. 1 is a view of a general mobile communication base station system adopting the above-described separate structure. As illustrated in FIG. 1, in the general mobile communication base station system, a digital unit is connected to a radio unit manufactured by an identical manufacturer to form a digital unit-radio unit network due to compatibility issues. For example, a digital unit A1 manufactured by a manufacturer A is connected to a radio unit A2 manufactured by the same manufacturer A without being connected to a radio unit B2 manufactured by a manufacturer B or a radio unit C2 manufactured by a manufacturer C. Similarly, a digital unit B1 manufactured by the manufacturer B is connected to the radio unit B2, and a digital unit C1 manufactured by the manufacturer C is connected to the radio unit C2.
Due to such equipment compatibility problems, a mobile communication provider cannot use low-cost equipment with high performance provided by manufacturers that independently supply only digital units or radio units when constructing a mobile communication base station system. Therefore, it is difficult for the mobile communication service provider to reduce cost of constructing the mobile communication base station system.
Furthermore, in the general mobile communication base station system as illustrated in FIG. 1, a digital unit-radio unit network including equipment manufactured by a particular manufacturer is controlled by an O&M server provided by the manufacturer. For example, the digital unit A1 and the radio unit A2 manufactured by the manufacturer A are controlled through an O&M server A3 provided by the manufacturer A. Similarly, the digital unit B1 and the radio unit B2 manufactured by the manufacturer B are controlled through an O&M server B3 provided by the manufacturer B, and the digital unit C1 and the radio unit C2 manufactured by the manufacturer C are controlled through an O&M server C3 provided by the manufacturer C.
Due to such equipment compatibility problems, a mobile communication service provider needs to control each digital unit-radio unit network including equipment manufactured by a particular manufacturer using an O&M server provided by the same manufacturer, and thus it is difficult for the mobile communication service provider to efficiently manage the entire system.